Cathodoluminescent phosphor viewing screens are known and widely employed for a variety of image display devices such as, for example, television and computer monitors.
Phosphor systems commonly employed for image displays include those which utilize a plurality of dis-similar phosphor materials to realize full color capable displays. For example, three color phosphor systems which provide discrete sub-pixel phosphor areas each of one of red, green, or blue photon emitting material are realized by multiple depositions, maskings, and patternings of the dis-similar phosphor materials. The multiple depositions, maskings, and patternings greatly complicates the fabrication process, adding a great amount of time, labor and cost to the process.
Phosphor screens for cathode ray tubes (CRTs) are usually deposited by the slurry method. A solution containing one of the three primary-color phosphors (i.e., red, green, blue), aqueous PVA and aqueous (NH.sub.4).sub.2 Cr.sub.2 O.sub.2 is made into a slurry and dispersed onto a rotating horizontal flat panel (the screen). The flat panel is spun until the slurry is evenly distributed and then it is exposed through a shadow mask. The unexposed regions are rinsed away in water. This process is then repeated for each of the other colors.
The slurry process described above is subject to problems such as inhomogeneous screening, pinhole formation during rinsing, cross-color contamination, and coagulation of particles. In addition, alignment of the color stripes must be maintained. These are a common shortcomings of the known art.
Accordingly, there exists a need for a means to provide for an improved multi-color phosphor system which may overcome at least some of the shortcomings of the prior art.
It is one purpose of the present invention to provide an image display faceplate with phosphor system which does not require the complex fabrication methods of the known art.
It is another purpose of the present invention to provide an image display viewing screen with associated multi-colored phosphor system wherein each of the plurality of dis-similar phosphor materials may be deposited (dispensed) as part of a single deposition step by employing a plurality of phosphor material dispensing means.
It is a further purpose of the present invention to provide a cathodoluminescent image display viewing screen faceplate having a plurality of recessed regions formed therein each for accepting a prescribed amount of one of a plurality of dis-similar phosphor materials.